Rock-drill



H. M. CHASE.

ROCK DRILL.

APPLICATION FILED JUNE 3. 1919.

Patented Sept. 14, 1920.

UNITED STATES PATENT OFFICE.

HARRY M. CHASE, 01? DENVER, COLORADO, ASSIGNOR'TO THE DENVER ROCK DRILL MANUFACTURING COMPANY, OF DENVER, COLORADO, A CORPORATION OF DELA- WARE.

Application filed June 3,

To all whom it may concern:

Be it known that I, HARRY M. CHASE, a citizen of the United States, residing at Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Rock-Drills, of which the following is a specification.

The present invention relates more particularly to rock drilling apparatus of that type in which the drilling motor is held to its work by extensible fluid actuated feeding means. As is well known to those skilled in the art, air under pressure is ordinarily utilized as the motive fluid, and this air pressure .may vary in different mines and under different conditions. Thus, one mine may have a system with high pressure; others of much lower pressure. Very often also where a long hose line is used that is tapped at different points, the pressure is greatly reduced toward the outer end. Under such circumstances, it often happens that the pressure is so low that the motor is not properly held to its work. For example,-assume that eighty pounds pressure in the hose line will supply sufficient air to hold the motor to its work and also furnish the proper amount for actuating the motor. If this same machine is connected to a hose line in which there is but forty pounds, the air will pass so rapidly through the motor that the pressure in the feeding means is reduced and may not hold said motor properly .to its work.

The primar object of the present invention is to prov de apparatus in which a sufficient pressure is obtained and maintained in the. feeding means to insure its proper functioning irrespective of the pressure of the motive fluid; supplied to the apparatus.

A further object is to so construct this mechanism that an over pressure in the feeding means is prevented.

Thepreferred embodiment of the invention is illustrated in the accompanying drawings, wherein 4 Figure l is a longitudinal sectional view through a well known form of rock drill, showing the improvements embodied therein.

Fig. 2 is a cross sectional view on the line 22 of Fig. 1 and on an enlarged scale.

Similar reference numerals designate cor- Speeifieation of Letters Patent.

ROCK-DRILL.

1919. Serial No. 301,450.

PatentedSep't.14, 19 20.

responding parts in all the figures of the illustrated at 7. The head also contains a tappet'8 against which the rear end of the drill steel abuts, and said tappet projects into the chamber 4. Mounted to reciprocate in, the chamber 4.is a piston, comprising 7 a head 9 having a reduced rearward extension 10. The head 9 is adapted to strike the tappet 8, and the latter transmits the blow to the drill steel 7 in a manner well understood.

The rear portion of the chamber 3 is provided with a receiving chamber 11 containing a rearwardly extending sleeve portion 12 and a forwardly extending sleeve portion 13, said two sleeve portions having their adjacent ends spaced apart to provide a port or passageway14. The reduced extension 10 has a peripheral channel 15 adjacent to its juncture with the head 9, and said extension operating in the sleeve ortion 12 and 13 is movable into and out o the latter and across the passageway or port 14. Supply passages 16 lead from the chamber 11 and open into the bore of the front portion of the sleeve 12 Another passageway 17 has its rear end opening into the bore of the sleeve 12, and also opens as shown .at '18 into the front portion of the piston'chamber 4. -Motive fluid is supplied to the-fichamber' 11 through a passageway 19 extending thereto from a valve casing 20.

Secured to the rear portion of the-drilling motor is motive fluid operated feedingthat the ports 28 and 29 are so arranged that when the port 29 is in communication with the passageway 25, the port 28 is out of communication with the passageway 19, and when said port 28 is in communication with the passageway 19, as shown in F ig. l, the port 29 is out of communication with the passageway 25. With this arrangement the motive fluid can be supplied tothe feeding means when the drilling motor is inactive, and when'said drilling motor is thrown into action, the supply of motive fluid through the passageway 25 is cut off.

In order to obtain an effective pressure in the feeding means 2124, when the pressure of the fluid supply is not sufficient, the following mechanism is employed. In the head between the cylinder member 3' and cylinder member 21 is a transverse chamber having portions 30 and 31 of different diameter. A port 32 aflords' communication between the rear end of the bone of the sleeve 13 and the inner end of the portion 30 of large diameter; and a port 33 affords communication between the opposite side of the inner end of the portion 30 with the inner end of the cylinder 21. A piston valve 34 is mounted to reciprocate in the cham ber 3031, and has portions corresponding in diameter to the different portions of said chamber, thereby forming a shoulder 35.

i The inner end of the portion 31. of the chamber has a port36 communicating with the cylinder 21, andthe outer end of the portion 35 of said chamber has a port 37 also in communication with the cylinder 21. A coiled spring 38 bears against the outer larger end of the valve 34, and is borne against by a plug 39 threaded into the outer end of the chamber. It will be noted that the rear extension 10 moves into and out of the sleeve 13, a pump structure thus being formed of which the sleeve 13 is the cylinder and the extension 10 is the piston.

The operation of the apparatus is as follows. \Vhen the machine is set up, the spur 24 is. placed against a suitable abutment, and the valve 26 is turned to permit the port 29 to communicate with the passageway 25. The motive fluid will thus enter the cylinder 21 and raise said cylinder and the drilling motor until stopped by' the abutment of the drill steel 7 against the front end of the tappet 8; If now the valve 26 is turned to the position shown,in Fig. l, the supply of motive fluid to the feeding means is cut off, but the supply to the drilling motor is opened by the port 28 registering with-the passageway 19. The drilIing motor is thus thrown into operation and as the piston reciprocates, it Willdeliver rapidly repeated blows upon the tappet 8, which blows will be transmitted to the steel 7 as well understood. Upon each rearward movement of the piston hammer the extension 10 will enter the pocket 13, thereby trapping the motive fluid which enters the same and highly compressing it. This motive fluid operating against the shoulder 35 will open the valve 34 against the pressure of the spring 38, and pass into the cylinder 21. As a consequence this structure is in effect a booster that will increase the pressure in the feeding cylinder above that in the supply line, and in the motor. It will be noted that this pressure will act against both ends of the piston valve 34 by reason of the open communication through the ports 36 and 37, and when said pressure reaches a predetermined' maximum the valve 34 will remain closed due to this pressure, plus the action of the spring 38. The force of said spring can be varied by adjusting the plug 39.

With this structure therefore an operative feeding pressure can be obtained irrespective of lowpressure in the hose line and drilling motor. In addition, it will be observed that besides acting as a pump the rear end of the extension entering the sleeve 13 will produce a cushion for the piston.

From the foregoing, it is thought that the construction, operation and many advantages of the herein' described invention will be apparent to those skilled in the art without further description, and it will be understood that various changes in the size, shape, proportion, and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of. the invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In drilling apparatus of the character described, the combination. with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feeding means, and means for increasingthe pressure of the fluid in the feeding means above that of the fluid supply.

2. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and delivering it therefrom to the feeding means, and means for increasing the pressure of the fluid in the feeding means above that of the fluid supply.

3. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under p1;essure to the motor and feeding means, and means for increasing the pressure of the fluid in the feeding means above that of the fluid supply and automatically determining said pressure in the feeding means. p

4. In drilling apparatus of the character described, the combination with a drilling motor, of fluid. actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feeding means, and means interposed between the motor and feeding means for increasin the pressure of fluid in the feeding means a ove that in the motor.

5. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feeding means, and means interposed between the motor and feeding means for increasing the pressure of fluid in the feeding means above that in the motor, and automatically governing the said pressure in the feeding means.-

6. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feedingmeans, and a pump for boosting the pressure in the feeding means.

7. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feeding means, a pump for boosting the pressure in the feeding means, and means actuated by the fluid in the feeding means for governing the pressure of such fluid.

8. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feeding means, a pump having a delivery passageway opening into the feeding means, and a valve controlling such passageway.

9. In drilling apparatus of the character describede, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid under pressure to the motor and feeding means, a pump havin a delivery passageway opening into the eeding means, a valve controlling such passageway, and means controlled by the pressure of fluid in the feeding means for governing the action of the valve. I

10. In drilling apparatus of the character described, the combination with a drilling motor, of fluid'actuated feeding means therefor. and means actuated'by the drillin motor for boosting the pressure'of th'e-flui in the feeding means above'that in the motor.

I 11. In drilling apparatus of the charac-' ter described, the combination with a drill- "der.

ing motor, of fluid actuated feeding means therefor, and a pump actuated by the drill ing motor for boosting the pressure of fluid in the feeding means above that in the motor.

. 12. In drilling apparatus'of the charac I terdescribed, the combination with a drilling motor includinga cylinder member and a piston operating therein, of'fluid actuated feeding means for the drilling motor, and a pump for delivering motive. fluid to the feeding means includlng a cylinder memher and a piston element operating therein, and carried by thedrilling motor piston.

13. In drilling apparatus of the character described, the combination with a drill-. ing motor, including .a cylinder member and a piston operating therein, of fluid actuated feeding means for the drilling motor, and

14.111 drilling apparatus of the character described the combination with a drilling motor, of fluid actuated feeding means therefor, means actuated by the drilling motor for boosting the pressure of the fluid in the feeding means above that in the motor, and means for controlling the pressure of fluid in thefeeding means. I

15. In drilling apparatus of the character described, the combination with a'drilling motor, of fluid actuated feeding means therefor, a pump actuated by the drilling motor for boosting the pressure of fluid in the feeding means above that in the motor, and-means for controlling the fluid 1 5 supplied by the pump to govern the pres sure of such motive fluid in the feeding] means.

16. In drilling apparatus of the charac-. ter described, the combination with a drill- .1 0 ing motor, of fluid actuated feeding means therefor, a pump actuated by the drilling motor for boosting the pressure of fluid 'in the feeding means above that in the motor, and a pressure controlled valve governing the passage of fluid from the pump to the feeding means.

17 ..In drilling apparatus of the character described the combination with a drilling motor, including a cylinder member and a piston operating therein, of fluid actuated feeding means for the drilling motor, and a pump for delivering motive fluid to the feeding means including a cylinder member at the rear end of the cylinder member,

a piston element on the rear end of the pispump to the feeding means.

18. In drilling apparatus of the character described, the combination with a drilling motor comprising a cylinder member having a rear supply reeciving chamber, said chamber having alined sleeve portions projecting-thereinto, with an opening between their their ends, and a hammer piston operating in the cylinder member and having an enlarged head and a reduced rearward extension that operates in the alined sleeve portions and moves across the said opening between them, of means for supplying motive fluid to the chamber, and means controlled by the' extension of vthe piston for distributing the motive fluid to opposite sides of the head.

y 19. vIn drilling apparatus of the character described the combination with a drilling motor comprising a cylinder member having a rear supply receiving chamber, said chamber having alined sleeve portions projecting thereinto, with an opening between their ends, and a hammer piston operating in the cylinder member and having an enlarged head and a reduced rearward extension that operates in the alined sleeve portions and moves across the said opening between them, of means for suppliyng motive fluid to the chamber, means controlled by the extension of the piston for distributing the motive fluid to opposite sides of the head, fluid actuated feeding means connected to the drilling motor, a passageway leading from the rear sleeve portion to the feeding means, and an automatic valve in the passageway.

20. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for separately supplying motive fluid to the feeding means and drilling motor, and means for delivering a portion of the fluid supplied to the drilling motor under increased pressure to the feeding means.

21. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuated feeding means therefor, means for supplying motive fluid .to the feeding means and drilling motor, a single valve for controlling the supply and cutting off that to the feeding means when the supply to the ,motor is open, and means for delivering a portion of the fluid supplied tothe drilling motor to the feeding means and increasing thd pressure thereof.

22. In drilling apparatus of the character described, the combination with a drilling motor, of fluid actuating feeding means therefor, means for supplying motive fluid to the feeding means and drilling motor, a single valve for controlling the supply and cutting off that to the feeding means when the supply to the motor is open, a cylinder element'formed in the rear portion of the drilling motor, a passageway leading therefrom to the feeding means, and an automatic pressure controlled valve governing the passage and actuated by the pressure in the feeding means, said drilling motor including a piston, the rear end of which enters and leaves the cylinder formed in the rear portion of the drilling motor.

23. In drilling'apparatus of the char-cater described, the combination with a motor comprising a cylinder member and a piston therein, of fluid actuating feeding means for the motor, a combined cushioning pocket and pump cylinder for the rear end of the piston, a passageway therefrom to the feeding means, and an automatic valve in said passageway controlling the passage of fluid therethrough.

In testimony whereof, I aflix my signature in the presence of two witnesses.

SOUTHARD JOHNSON, EDWARD L. OLDHAM. 

